Add sql script to generate tables

database/001_create_tables.sql

@@ -0,0 +1,18 @@
+CREATE TABLE
+    users (id SERIAL PRIMARY KEY, name VARCHAR(255) NOT NULL);
+
+CREATE TABLE
+    workouts (
+        id SERIAL PRIMARY KEY,
+        user_id INTEGER NOT NULL REFERENCES users (id) ON DELETE CASCADE,
+        created_at TIMESTAMP NOT NULL DEFAULT NOW ()
+    );
+
+CREATE TABLE
+    cadence_readings (
+        id SERIAL PRIMARY KEY,
+        workout_id INTEGER NOT NULL REFERENCES workouts (id) ON DELETE CASCADE,
+        created_at TIMESTAMP NOT NULL,
+        rpm INTEGER NOT NULL,
+        CONSTRAINT unique_cadence_reading_per_workout_time UNIQUE (workout_id, created_at)
+    );